Depletion and Decline Curve Analysis in Crude Oil Production

11 Abbreviations AAPG American Association of Petroleum Geologists, international association of professional geologists working in the petroleum or energy minerals fields API American Petroleum Institute, U.S. trade organisation for oil and gas industry BGR Bundesanstalt für Geowissenschaften und Rohstoffe, the German Federal Institute for Geosciences and Natural Resources bpd barrels per day [b/d], common unit for measuring production DAP Depletion At Peak, the depletion rate of remaining reserves that occur when the onset of decline is reached for a field CERA Cambridge Energy Research Associates, consulting firm specialized in advising compa- nies and governments on energy markets, geopolitics, industry trends and strategy EIA Energy Information Administration, independent statistical agency within the U.S. De- partment of Energy devoted to providing policy-independent data, forecasts and analysis EUR Estimated Ultimate Recovery, synonym to URR Gb Gigabarrels, equivalent to one billion barrels IEA International Energy Agency, intergovernmental energy organization founded by the Or- ganisation for Economic Co-operation and Development (OECD)-countries NGL Natural Gas Liquids, liquid side products from natural gas processing NGPL Natural Gas Plant Liquids, same as NGL NPD Norwegian Petroleum Directorate OIP Oil In Place, all oil present in an underground structure OIIP Oil Initially In Place, synonym to OIP and OOIP OOIP Oil Originally In Place, synonym to OIP and OIIP OPEC Organization of Petroleum Exporting Countries, an intergovernmental organisation of the worlds' dominating oil exporting countries RF Recovery Factor, the recoverable percentage of OIP RPR Reserve-to-Production Ratio, quotient of remaining reserves and production used to de- scribe how long the reserves will last with current production rate SPE Society of Petroleum Engineers, professional organisation engineers, scientists, managers and educators in the oil and gas exploration and production industry URR Ultimate Recoverable Resources, the upper limit for cumulative production USGS United States Geological Survey, scientific agency in the U.S. government devoted to geo- sciences and natural resources